Discharge gate apparatus



Feb. 27, 1962 W. G. DAVENPORT ETAL DISCHARGE GATE APPARATUS Filed May26, 1960 2 Sheets-Sheet 1 O R J P Q 7 P le 0 L2 /34 40 I5 35 L 33 T k 014 0 0 H31.

'V' 1 INVENTOR. 39 34 WILLIAM G. DAVENPORT ROBERT K. HAMPTON Y ALAN M.KATZEN B ATTORNEY Feb. 27, 1962 w. G. DAVENPORT ETAL 3, ,921

DISCHARGE GATE APPARATUS Filed May 26, 1960 2 Sheets-Sheet 2 .3 Fig. 5

INVENTOR. WILLIAM G. DAVENPORT ROBERT K. HAMPTON ALAN M. KATZEN gigATTORN EY rates This invention relates generally to drained gates forcontrolling the delivery of bunkered material to any suitable receivingapparatus. Commonly gates of the type to be described are installedbelow bunkers which hold material containing a substantial amount ofwater, as for example, coal bunkers wherein the stored coal alsocontains coal wash water, and hot ash storing bunkers wherein the ashcontained therein has been quenched and, therefore, also contains asubstantial amount of water. For purposes of illustration, the presentinvention hereinafter described is illustrated in the drawings asembodied in an ash gate.

In order to adequately quench the hot ash deposited in the bunker,immediately below which the gate according to the invention is located,substantial amounts of water are employed and the gate drainageapparatus must be capable of carrying ofii this water without spilloveror overflow onto the floor underlying the gate. In some applications,the volume of quench water required to be drained may readily exceedfifty gallons per minute and presently known drained gate structures aregenerally unable to handle such a water volume. Moreover, when the standof bunkered material is of any substantial height, a considerable headof water may exist in the bunker. Since the bunker closing gate isgenerally spaced fairly closely below the bottom of the bunker dischargechute, as for example approximately one-eighth of an inch below, it willbe appreciated that bunkered water under any appreciable head will bedischarged laterally outward through the small clearance between thechute bottom and the top of the gate at a relatively high velocity. Withgates of the usual type having upward and outwardly sloped side walls,the drain water flowing laterally outward across the top of the gatebottom at high velocity can flow right up the side walls and over thesides of the gate and thereby fall to the floor below. Since thiscondition arises as a consequence of the velocity of the flowing drainwater, it may occur even in those cases where the gate would otherwisenormally be able to handle the volume of drain water.

Thus, the instant invention contemplates the solution of two problems,namely the provision of a drained gate with means for draining largevolumes of water from the bunkered material above the gate, and also theprovision of means for preventing high velocity drain water fromescaping the drainage system. While it may at first be considered thatthe two problems solved by the present invention are essentiallyindependent ones, this is not in actuality the case and the means forovercoming the volume drainage requirements problem also contributes tothe solution of the velocity problem. Accordingly, it is a primaryobject of this invention to provide a novel drained gate apparatuswherein means are provided for substantially increasing the ability ofthe gate to handle large quantities of drain water and to simultaneouslyprevent the escape of the drain water from the drainage system.

Another object of this invention is to provide novel drained gateapparatus which includes means for confining high velocity drain waterto the drainage system and preventing spillover or spraying thereof outof the drainage system.

Yet another object of this invention is to provide novel drained gateapparatus of substantially increased capacity atent nice 3,022,921Patented Feb. 27, 1962 for handling drain water by structural changes tothe gate which do not necessitate changes to other parts of theapparatus.

Still another object of the present invention is to provide noveldrained gate apparatus capable of handling very large quantities ofdrain water by employing a construction which utilizes the principle ofgravitic flow.

The foregoing and other objects of the invention will become apparentfrom a reading of the following specification in conjunction with anexamination of the appended drawings, wherein:

FIGURE 1 is a side elevational view of the drained gate according to theinvention installed upon an ash bunker to close the discharge chutethereof;

FIGURE 2 is a top plan view of the drained gate according to theinvention as would be seen when viewed from above with the overlyingbunker removed, but with the bunker chute remaining;

FIGURE 3 is a transverse sectional view through the drained gateaccording to the invention as would be seen when viewed along the lines33 of FIGURE 2;

FIGURE 4 is a longitudinal sectional view through the drained gateaccording to the invention as would be seen when viewed along the lines4-4 of FIGURE 2;

FIGURE 5 is an enlarged fragmentary view, in section, of that portion ofthe apparatus within the phantom circle on FIGURE 3.

In the several figures, like elements are denoted by like referencecharacters.

Turning now to the drawings and considering first the views of FIGURES 1and 2, there will be seen a storage bunker 1-0 whose inside walls arelined with a refractory material 11, such as fire brick, and which hasaffixed to the bottom opening thereof a bunker chute 12 extendingvertically downward therefrom and having an open bottom adapted to beopened or closed by the shiftable gate 22. The bunker chute 12 isprovided with the vertically extending front wall 13, rear wall 14 andpair of opposite side walls 15. Formed integrally with the chute 12 atthe top thereof is a peripherally extending top mounting flange 16apertured with the bolting holes 17 and by means of which the chute 12may be bolted to the bottom of the bunker 10. As best seen in the viewof FIGURE 4, the outer surfaces of the front and rear chute walls areprovided with substantially horizontally extending reinforcing flangesdesignated as 18 on the rear wall 14 and designated as 19 on the frontwall 13.

As best seen in FIGURES 3 and 4, integrally formed with or subsequentlysecured to the chute side walls 15 on the outer surfaces thereof andextending at an inclination to the horizontal are a pair of side wallmounted inclined tracks 20. The tracks Zil, along which the gate 22 isshiftable in a manner to be subsequently described, extend from a pointto the right of the chute rear wall 14 over toward the left on adownward inclination along the chute side walls 15 to a point just shortof the chute front wall 13, then turning upward through the shortupturned section 21 and terminating at the front Wall reinforcing fiange19. The short up-turned track section 21 proximate the chute front wall13 acts as a stop to the forward motion of the gate 22 by preventing thegate carrying rollers 33 from further rotation in the direction of thechute front wall.

As best seen in the showings of FIGURES 3 and 5, the bunker chuteclosing gate 22 is generally of U-shape in cross section, the bottomregion of the U being of some what modified construction. The lowerregion of the gate 22 is seen to be formed of a horizontally extendingbottom portion 23 having a pair of up-turned side edges 24 whichtogether form a trough lined with a refractory material 25. Extendinglaterally outward from each of the up-turned edges 24 is an outwardlyturned generally horizontally extending portion 26 which each themselvesturn vertically upward generally parallel to the chute side walls andterminate in horizontally extending flange portions 28 extending inopposite direction from the up-turned portions 27, so that each flange28 extends inward toward the chute side walls and outward therefrom. Theinward projecting portions of the flanges 28 are observed to closelynon-engagingly underlie the tracks mounted on the outside of the chuteside walls 15, and also to form with the below-lying gate verticalportions 27 and horizontal portions 26 a pair of side drainage channels29. This same drainage channel structure is also formed at the back endof the gate 22, as best seen in the showing of FIGURE 4, so that thedrain channel 29 is continuous around the sides and rear of the gate 22.The front end of the gate 22, which is observed in FIG- URES l and 4 asprojecting into the drain box 38, is not provided with the drain channelforming vertical portions 27 or horizontal flange 28, but is insteadprovided with a drip ledge 30 so that the water draining from the bunkermay flow through the drain channels 29 and along the top surface of thegate 22 toward the drain box 38 and bedischarged thereinto over the dripledge 30.

Extending vertically upward from the side flanges 28 are the gate 22side walls 31, to the inner sides of which are rotatably journalled therollers 33 seated upon and riding along the tracks 20 secured to thechute side walls 15. Formed along the upper edge of each of the sidewalls 31 are a plurality of teeth which form solid toothed racks 32.Disposed above the racks 32 and in meshed engagement therewith are theteeth of a pair of pinions 36 fixedly mounted upon a rotatable shaft 34journalled in bearings 35 carried by the upper portions of the trackstructures 20 located to the right of the chute rear wall 14. The pinionshaft 34, as best'seen in FIGURE 2, extends for a distance beyond thechute side walls on one side and has affixed thereto a chain wheel 37 bymeans of which the shaft 34 and pinions 36 may be rotated to cause theteeth of the pinions 36, which are intermeshed with the solid toothedracks 32, to drive the entire gate 22 to the right in order to open thechute bottom or to the left to close the chute bottom, the entire gate22 being shifted along the tracks 20 by means of the rollers 33journalledin the gate side walls 31.

Depending from and secured to the bunker chute front wall reinforcingflange 19 by means of the bolts is the enclosed drain box 38 having anoutlet 39 at one end thereof and being provided with a side opening 41into which the drip ledge 30 of the gate 22 projects when the gate isclosed. The drain box 38 is inclined, as best seen in the showing ofFIGURE 3, so that the collected water tends to flow by gravity outthrough the outlet 39, which in general will be coupled to a run-offsystem, such as a run-off gutter. The lower edge of the drain box sideopening 41 which is normally disposed immediately below the gate dripledge 38 is provided with an inwardly somewhat down-turned flange 42 toprevent relatively high velocity drain water running oif of the gatedrip ledge from flowing around the curved bottom of the drain box 38 andupwardly out through the side opening 41. Similarly, avsecond flange 42is formed on the inside of the drain box 38 extending substantiallyhorizontally and parallel to the side opening flange but being disposedalong the drain box wall remote from the gate 22. Understanding now thebasic structure of the apparatus, the following discussion of the mannerin which the apparatus achieves the aforedescribed desired functionswill be readily understood.

"gatesof this'type. In the usual gateythe horizontal and verticalportions 26 and 27 are absent and there exists generally in their placea diagonally upward sloping side wall portion which bridges between thetops of the upturned edges 24 and the horizontal flanges 28, the inwardextending projections of the flanges 28 also being absent. The drainagearea thus provided is of generally triangular crosssection lying betweenthe diagonally upward sloping portion just mentioned and the outsidesurface of the lower edge of the bunker chute. The smaller area of thedrain channel cross section in the usual case, therefore, restricts thevolume of water that can pass into the drain box at any given instant oftime and frequently results in the bunker drain water overflowing thesides of the gate.

The change in configuration of the gate bottom cross section in thechannel region significantly increases the drain channel cross-sectionalarea and hence permits larger volume discharges from these channels intothe drain box thereby reducing and generally eliminating any tendencytoward an overflow condition. Additionally, the inclination of thetracks 20 upon which the gate rollers 33 are'disposed, causes the entiregate 22 to be inclined toward the drain box 38 so that water drainingfrom the bunker is accelerated toward the drain box 38 and does not tendto pile up in the side and end drainage channels 29. The inclination ofthe gate 22 in this fashion dictates that the bunker chute front wall 13be of somewhat greater vertical extent than the bunker chute rear wall14 in order to maintain substantially the same clearance at all pointsbetween the chute bottom and the top surface of the bottom portion ofthe underlying gate 22 so that any'tendency toward Washing some of thebunker material into the drain box'is minimized.

Observation of FIGURES 3, 4 and 5 reveals the relatively small clearancebetween the peripherally extending bottom edge of the bunker chute 12and the underlying outwardly turned horizontal portions 26 of the gatebody bottom region. As earlier mentioned, this relatively smallclearance causes the bunkered water to flow outward into the channels 29at asubstantial velocity which in the case of the usually constructedgate would result in immediate water spillover and spraying onto thefloor below regardless of the water volume handling capabilities of thegate. Such spillover and spraying cannot occur with the illustrated gateconstruction because it will be appreciated that this high velocitylaterally flowing water will be turned up the channel 29 side walls 27and then turned inwardly against the lower outer surface of the chutebottom by means of the inward projecting portions of the horizontalflanges 28. The high velocity drain water is thus confined to thedrainage channels 29 through which it flows along the downwardly slopingchannel bottoms 26 toward and into the drain box 38. The tendency towardsplashing or spraying of water out of the channel 29 is further reducedby causing the inwardly projecting portions of the horizontal flanges 28to relatively closely underlie the bottoms of the tracks 20 and thebottom of the chute rear wall reinforcing flange 18 to thereby provide avery narrow opening therebetween through which the spray findsitextremely diflicult to pass.

It will, of course, be realized that the particular crosssectional shapeof the closure gate 22, as for example illustrated in FIGURE 3, is notnecessarily limited to that illustrated but may be modified fordifierent purposes while still incorporating therein the advantages ofthe aforedescribed invention. By way of illustration, it will beappreciated that a gate designed to close the bottom of a coal bunkerneed not be formed with the bottom channel structure including thebot-tom horizontal portion 23 and up-turned side flanges 24 since in theillustrated case the trough so formed is utilized to accommodate therefractory lining material 25 to adequately withstand the heat of thestill hot bunkered ash material. Elimination of this channel is readilyachieved by merely'eliminating the side portions 24 and forming the gatebottom 23 as a continuous extension of the horizontally outward turnedportions 26. Similarly, the cross-sectional area of the drain channel 29may be materially further increased if desired by extending the outwardturned portions 26 to points underlying the side walls 31 and shiftingthe upward turned portions 27 outward substantially flush with the outeredge of the gate side walls 31. Moreover, the inclination of the tracks20 along which the gate 22 is shiftable may be more or less than thatillustrated in the,figures depending upon the particular requirements ofthe given installation.

Having now described our invention in connection with a particularlyillustrated embodiment thereof, it will be understood that modificationsand variations will occur from time to time to those persons normallyskilled in the art without departing from the essential scope or spiritof the invention, and, accordingly, it is desired to claim the samebroadly as well as specifically as indicated by the appended claims.

What is claimed as new and useful is:

1. Under-bunker drained gate apparatus comprising in combination, achute projecting downward from the bunker, a chute bottom closure gateshiftable between chute opening and chute closing positions, said gatehaving a bottom portion the top surface of which closely underlies thelower peripheral edge of said chute in spaced relation thereto when saidgate is in chute closing position to define a peripherally extendingopening therebetween, a drainage channel carried by said gate andcommunicating adjacent to the bottom thereof with said peripherallyextending opening to thereby receive bunker held water passing outwardthrough said opening, a drainage channel discharge means for permittingthe escape of drain water out of said drainage channel, and meansoperatively associated with said drain channel to prevent the drainwater from escaping said drain channel except through said dischargemeans.

2. The apparatus according to claim 1 wherein said drainage channeldischarge means comprises a drip ledge at one end of said gate overwhich the drain water flows out of said drainage channel, and anenclosed drain box secured to said chute, said drain box being aperturedto permit penetration of said gate drip ledge thereinto when said gateis in chute closing position.

3. The apparatus according to claim 2 wherein said drain box at thelower edge of the drip ledge aperture is provided with an in-turnedflange to prevent drain water from escaping through the aperture bydeflecting the same back into the drain box.

4. The apparatus according to claim 1 wherein said drainage channel isinclined to accelerate the flow of drain water toward said dischargemeans.

5. The apparatus according to claim 1 wherein said drainage channelextends about a substantial portion of the gate bottom periphery and incommunication with said opening, the remainder of the gate bottomperiphery comp-rising said drainage channel discharge means.

6. The apparatus according to claim 1 wherein said drainage channelcomprises a lateral extension outward beyond the chute side walls ofsaid gate bottom top surface, said surface extension then being turnedupward for a distance and terminating in a surface portion in-turned andprojecting toward the outer surface of the chute side walls, wherebyhigh velocity drain water passing outward through said opening isdeflected by said surface extensions backward toward the outside surfaceof said chute and falls back down into said drainage channel, saidin-turned surface portion comprising at least a part of said means forpreventing escape of drain water from said drainage channel.

7. The apparatus according to claim 6 wherein said means for preventingescape of drain water from said drainage channel further includesflange-like elements projecting laterally from the side walls of saidchute in closely spaced overlying relationship to the drainage channelin-turned portion which projects toward the outer surface of said chuteto thereby prevent water spray from escaping out of the drainage channelthrough the opening between the chute outer surface and the saidinturned portion projecting theretowards.

8. The apparatus according to claim 6 wherein the side walls of saidchute carry a pair of parallel disposed tracks inclined at an angle tothe horizontal, and wherein said gate carries a plurality of rollersseated upon said tracks for movement therealong and for inclining saidgate carried drainage channel at an angle tothe horizontal in accordancewith the angle of said tracks, the inclination of said tracks being insuch sense as to cause accelerated flow of drain water toward saiddischarge means.

9. The apparatus according to claim 7 wherein the flange-like elementsprojecting laterally from the side walls of said chute comprise a pairof parallel disposed tracks inclined at an angle to the horizontal, andwherein said gate carries a plurality of rollers seated upon said tracksfor movement therealong and for inclining said gate carried drainagechannel at an angle to the horizontal in accordance with the angle ofsaid tracks, the inclination of said tracks being in such sense as tocause accelerated flow of drain water toward said discharge means.

10. The apparatus according to claim 8 further including gate stop meansoperative to prevent further shifting motion of said gate along saidtracks when said gate is in chute closing position.

11. The apparatus according to claim 8 wherein the lowermost points ofsaid inclined tracks are turned sharply upward to provide roller stopmeans effective to prevent further shifting motion of said gate alongsaid tracks when said gate is in chute closing position.

12. The apparatus according to claim 8 wherein said drainage channeldischarge means comprises a drip ledge at one end of said gate overwhich the drain water flows out of said drainage channel, and anenclosed drain box secured to said chute, said drain box being aperturedto permit penetration of said gate drip ledge thereinto when said gateis in chute closing position.

References Cited in the file of this patent UNITED STATES PATENTS1,360,805 Sherman et al Nov. 30, 1920 1,561,761 Allen Nov. 17, 19252,238,296 Stock Apr. 15, 1941

